The present invention relates to technology of causing a television receiver to display a high-quality image by connecting an image processing device with the television receiver through a communication channel. In particular, the invention relates to technology suitably used when a communication channel interface is a high-definition multimedia interface (HDMI). The term “image processing device” used herein refers to a device which subjects an image signal obtained by a tuner to high-quality image processing.
An increase in the definition of an image displayed on an existing television receiver has been demanded. To deal with this demand, an image processing device has been studied which is connected to an external input of a television receiver through a cable to allow a high-quality image to be displayed on the display screen of the television receiver.
When connecting the image processing device to the external input of the television receiver and displaying a high-quality image from the image processing device on the display screen of the television receiver, it is necessary for the user to switch the display screen of the television receiver to an external input screen. When changing the program or adjusting the image quality (e.g. brightness, contrast, color depth, or hue) of the high-quality image displayed on the display screen, it is necessary to change the channel or adjust the image quality of the image processing device.
Therefore, when causing the television receiver to display the high-quality image by remote control, it is necessary to supply power to the television receiver using a remote controller for the television receiver (hereinafter called “television remote controller”), switch the display screen to the external input screen, and change the channel of the image processing device using a dedicated remote controller for the image processing device (hereinafter called “dedicated remote controller”). Specifically, the user must selectively operate the television remote controller and the dedicated remote controller when viewing television broadcasting.